FLAPPER VALVE ADAPTOR FOR A ROOF VENT AND METHOD OF INSTALLING THE SAME

摘要

An adaptor for a passive roof vent is presented having a base securable to a roof deck and an integrally moulded stepped collar extending from the base on one side for connecting to different air duct sizes which defines a discharge end for an air flow passageway. A central well is defined by the collar adjacent to and below the base and is open towards the other side of the base from said one side and has a hinge pin to define a pivot axis for at least one flapper valve retained in the well below said base. At least one flapper valve is hinged to the hinge pin and pivots about a closed position to which the flapper valve is biased by gravity and an open position in which the flapper valve is opened by air pressure from below within said air flow passageway. In this way the flapper valve, remains partially within said well when said flapper valve is open to present a low profile assembly. A method of installing such an adaptor is also comprehended.